蛋鸡产蛋期饲养技术要点

蛋鸡词养周期较长,一般可分为育雏期、育成期、产蛋期等阶段,其中产蛋期最长,也是蛋鸡养殖盈利的重要时期,现代高产蛋鸡产蛋期鸡只身体负荷大,如果词养技术跟不上会严重影响鸡只健康状况和生产性能。从现实看,蛋鸡从业者饲养管理水平参差不齐,即便是大型规模养殖场,精细化饲养也做得不到位,造成鸡只体况不佳、鸡蛋质量差、产蛋率低等问题,小、散户更为明显。本文结合生产实际,重点从词养、营养供给方面对高产蛋鸡产蛋期词养技术进行了总结归纳。     

Release of heat, moisture and carbon dioxide in an aviary system for laying hens.

1. Production of total heat, divided into sensible and latent heat, together with carbon dioxide and animal activity were determined at different ambient temperatures under full-scale conditions in an aviary system with loose-housed laying hens. 2. Sensible heat production decreased approximately linearly with increasing ambient temperature and was lower during the day than at night. One explanation may be that some sensible heat produced by the hens was converted to latent heat by evaporation of moisture due to increased activity of the hens during the day (scratching in the bedding and drinking/waste water). 3. Latent heat production increased with increasing ambient temperature and was higher during the day than at night. This confirms that the hens, by agitating the bedding during the day and by spilling drinking water, transferred some sensible heat to latent heat by evaporation. 4. Total heat production decreased with increasing temperature because the hens by thermoregulation decreased their metabolism in order to maintain a constant body temperature. The difference between day and night values of total heat production was less pronounced than in the case of sensible and latent heat. In comparison with current guidelines the measurements showed a higher total heat production (22% higher at 20 degrees C). 5. There was a large diurnal variation in carbon dioxide production, closely correlated to measured animal activity; on average carbon dioxide production during the 12-h dark period was only 66% of the production during the day.     

Climatic adaptation of laying hens

Summary Three hundred Warren Isabrown female day old chicks were raised for 18 weeks in 3 distinct artificial climates described as temperate (20°C, 60% RH), hot dry (32°C, 40% RH) and hot humid (32°C, 90% RH). At 18 weeks each group was divided into 3 and re-allocated to 3 similar air-conditioned laying rooms as during the growing period. Different diets were fed to the 3 groups up to 18 weeks. The energy needed in order to produce the same average live body weight at 18 weeks was similar in all the 3 climatic chambers. The effect of treatments in the growing period was not significantly different (P>0·05) for most of the parameters subsequently measured during the laying period. The exception was the body weight gain between 18 and 38 weeks and the food and energy intakes. However, apart from the sexual maturity, all these parameters were negatively influenced (P<0·05) by the effect of hot climates during the laying period irrespective of method of rearing. The results of this study seem to indicate that ambient temperature experienced during the first 18 weeks after hatching has little effect on subsequent productivity and that rearing birds at high ambient temperature does not acclimatise them to these conditions better than rearing them under temperate conditions.

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Adaptacion Climatica De Gallinas Ponedoras

Resumen Se leavantaron 300 pollitas de un día de nacidas, Warren Isabrown, por 18 semanas en 3 climas diferentes; templado (20°C, 60% HR), seco caliente (32°C, 40% HR) y caliente húmedo (32°C, 90% HR). A las 18 semanas cada grupo fue dividido en 3 y re-instalado en 3 cuartos de postura con aire acondicionado durante el período de crecimiento. Los 3 grupos recibieron diferentes dietas hasta las 18 semanas. La energía necesaria para producir el mismo peso promedio a las 18 semanas fue el mismo en las tres cámaras climáticas. El efecto del tratamiento durante el período de crecimiento no fue significativamente diferente (P>0·05) para la mayoría de parámetros medidos subsecuentemente durante el peródo de postura. La excepción fue el aumento en peso corporal entre las 18 y 38 semanas y la energía consumida. Sin embargo, aparte de la madurez sexual, todos los parámetros fueron afectados negativamente (P<0·05) por el efecto de los climas cálidos durante el período de postura, irrespectivamente del manejo. Los resultados de este estudio parecen indicar, que la temperatura ambiente experimentada durante las primeras 18 semanas después del nacimiento, tuvo poco efecto sobre la productividad y que la crianza de aves a temperatura ambiente alta, no las aclimata para esas condiciones mejor que levantandolas bajo un clima templado.

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Adaptation Climatique De La Poule Pondeuse

Resumé Trois cents poussins femelles d'un jour de souche Warren Isabrown ont été élevés jusqu'à l'âge de 18 semaines dans 3 climats artificiels distincts, respectivement tempéré (20°C, 60% HR), chaud sec (32°C, 40% HR) et chaud humide (32°C, 90% HR). A l'âge de 18 semaines chaque lot d'oiseaux a été divisé en trois et réparti à nouveau en 3 cellules de ponte conditionnées de la même façon que les salles de croissance. Différentes rations alimentaires sont nourries aux oiseaux jusqu'à l'âge de 18 semaines. La consommation d'énergie nécessaire pour produire le même poids vif à 18 semaines a été sensiblement égale dans les 3 climats. L'effet des traitements en période de croissance n'a pas été significativement différent (P>0·05) sur la presque totalité des paramètres étudiés en ponte, exception faite du gain de poids vif 18–38 semaines, des ingérés alimentaires et énérgétiques. Par contre, à l'exception de la maturité sexuelle, tous ces paramètres ont à chaque fois été influencés négativement (P<0·05) par les effets des climats chauds en période de ponte, indépendamment du climat d'élevage. Les résultats de cette expérience semblent indiquer que la température expérimentée pendant les 18 premières semaines après l'éclosion a eu peu d'effet sur la productivité ultérieure, et que l'élevage des oiseaux à hautes températures ambiantes ne leur confère pas une meilleure acclimatation à ces mêmes conditions que lorsqu'ils sont élevés en milieux tempérés.

     

Space needs of laying hens

1. Videotapes of hens under various conditions were used to measure the amount of space used by hens performing common behaviour patterns.

2. When turning, hens used 540 to 1006 cm², when stretching wings 653 to 1118 cm², when wing flapping 860 to 1980 cm², when feather ruffling 676 to 1604 cm², when preening 814 to 1270 cm² and when ground scratching 540 to 1005 cm².

3. All these measurements are above the 450 cm² bird recommended as the minimum space allowance by current EC regulations, which therefore do not ensure adequate hen welfare.     

Fluoride tolerance of laying hens

1. One thousand Silver Grey Hyline hens were given drinking water containing 5 concentrations of added sodium fluoride (0, 6, 10, 14 and 20 mg/1) over a 17‐week growth and 57‐week laying period. The natural fluoride content of the water was 0–21 mg/1 during the growing period and 0–29 mg/1 throughout lay.

2. During the rearing phase, efficiency of food utilisation and mortality were not significantly affected by the fluoride concentration of the water. Weight gain and food intake decreased in the 10 and 14 mg/1 fluoride treatments.

3. During the laying period, the fluoride content of the water had a significant effect on egg production, but eggshell breaking strength was not significantly influenced.

4. Post mortem analyses, carried out at the end of lay (74 weeks of age), showed that carcase weight and the fluoride content of the os femur increased significantly as the fluoride concentration in the water increased; the increase in bone fluoride followed a linear pattern.

5. Histopathology showed no evidence of changes in the livers or kidneys; liver weights and breaking strength of the os femur were unaffected by the amount of fluoride consumed.

6. The data showed that under commercial conditions, laying birds can tolerate ingesting 4–453 mg fluoride/day for up to 74 weeks.     

蛋鸡产蛋后期的营养调控

蛋鸡产蛋后期精准的营养调控可延缓蛋鸡的衰老,延长产蛋期,提高经济效益.本文从能量、蛋白质、维生素、矿物元素的营养需要等方面对蛋鸡产蛋后期的营养调控进行总结,以期能够对产蛋鸡后期的营养调控提供参考.     

维生素E对蛋鸡产蛋后期产蛋性能和蛋品质的影响

文章旨在研究日粮中不同梯度维生素E添加水平对蛋鸡产蛋后期产蛋性能和蛋品质的影响.试验选择60周龄罗曼白壳商品蛋鸡300羽,试验随机分为5组,添加水平分别为0(对照组),30、60、120、240 mg/kg,每组6个重复,每个重复10羽鸡,预试期1周,正试期8周.结果表明:与对照组相比,蛋鸡产蛋后期日粮中添加120 m...     

Behavioural responses to different floor space allowances in small groups of laying hens

Under Council Directive 1999/74/EC, minimum space allowances per laying hen range from 550 cm(2) in unfurnished cages to 1111 cm(2) in alternative housing, and to 40,000 cm(2) outdoors for free-range hens. In official reports on the welfare of laying hens, there is recognition that knowledge of their space requirements is inadequate. This experiment studied expression of behaviour, including spacing, in five groups of six and one group of five ISA Brown hens aged 21-33 weeks in an adjustable test pen providing 600, 2400, 4800, 7200, 9600, and 12,000 cm(2) floor area per hen. Each group was tested with every treatment. Home pens provided 2400 cm(2) per hen. The main aim was to identify a hypothetical point at which mutual repulsion equals mutual attraction (a 'broken stick' response). Sequencing of treatments was according to a Latin square design, daytime tests lasted 2 h and had no feeder or drinker present, and overnight tests were done with 2400, 7200 and 12,000 cm(2) per hen with a feeder and drinker present. Groups were video-recorded from above to allow repeated measurements of spacing and other behaviours. In daytime tests, the relationship between mean distance to nearest neighbour and floor space allowance was asymptotic, rather than a 'broken stick'. The steepest part of the response was between 600 and 4800 cm(2) per hen. Changes in other behaviours were greatest between 600 and 2400 cm(2), and there was no significant change above 7200 cm(2). Spacing behaviour responses at night were the same as by day. It is concluded that any space allowance of less than about 5000 cm(2) per hen imposes at least some constraint on free expression of behaviour, and that hens would benefit from any increase above the current minimum 1111 cm(2) usable area in alternative housing.     

产蛋鸡住白细胞原虫病与禽霍乱的混合感染

山东省临沂市某蛋鸡场于2005年3月3日购进海兰鸡5200只，鸡群按常规饲养，饲养方式为笼养，根据当地常发病情况进行了鸡马立克氏病、鸡新城疫、传染性法氏囊病、鸡痘、传染性支气管炎、传染性喉气管炎、产蛋下降综合征等的防疫，但未免疫禽霍乱疫苗。9月28日即209日龄时开始发病死亡，每天死鸡3～10只不等，最多死鸡每天达35只，产蛋率从93％下降到85％，软壳蛋、粗壳蛋增多，蛋壳色泽变淡，用盐酸环丙沙星饮水治疗，病情未得到控制，且不断加重。发病6d时间内死亡121只鸡，死亡率达2．33％。并且笼底层鸡死亡率比上层的鸡高。根据发病情况、临床症状、病理剖检变化、实验室检查等，确诊本病例为鸡住白细胞原虫病与禽霍乱的混合感染。     

The correct nutrition of laying hens

合理的营养在现代产蛋母鸡发挥产蛋遗传潜力和蛋品质量上起着一定的作用.此外,每枚鸡蛋的饲料成本占其生产成本的65％～70％.因此,产蛋母鸡的营养方案在决定鸡蛋生产企业的总体利润和成功上非常关键.     

Comparison of the coagulation profile of fatty liver haemorrhagic syndrome-susceptible laying hens and normal laying hens

1. The rate of thrombin generation in plasma from Fatty Liver Haemorrhagic Syndrome-susceptible laying hens (FLHS, UCD-003) is more rapid than in plasma from age-matched normal Single Comb White Leghorn (SCWL) laying hens. 2. The rate of thrombin generation in plasma was determined by measuring the biological activity of the specific coagulation proteins, Factors V, VII, VIII, IX and X. 3. The higher activity of Factors V, VII and X in FLHS-susceptible laying hens compared with normal SCWL hens remained consistent after plasma lipid concentrations were reduced. 4. Analysis of the fatty acid composition of plasma phospholipids showed that in normal SCWL laying hens phosphatidylethanolamine contained C18:3n3 whereas it contained C20:3n3 in FLHS-susceptible laying hens. 5. The results suggest that alterations in the composition of the phospholipids that are essential cofactors in the biochemical reactions involved in thrombin generation may be a contributing factor in the development of FLHS.     

Behaviour of laying hens in cages with nest sites

1. Behavior of ISA Brown hens was compared in cages with and without nest sites provided, to determine the characteristics necessary for such nest sites and whether part of the existing cage area could be modified to form an acceptable nest file. 2. There were 5 treatments: control (C); a wooden surround in one rear corner of the cage (S); a fiberglass rollaway hollow in one rear corner of the cage (H); a hollow and a surround (H/S); a nest box attached to the back of the cage, containing a hollow (N). 3. Use of rollaway hollows was limited, unless they were blocked and wood shavings were added, when 55 to 60% of eggs were laid in them. There were also problems with soiling of hollows. 4. When hollows were blocked, most hens used them in treatments H/S and N, suggesting that substrate and surroundings both contributed to acceptability of nest sites. 5. Pre-laying behaviour in sites within the cage was disturbed and sometimes abnormal. In addition, these sites were not used for other activities, thus limiting the space available. 6. For pre-laying behaviour to be expressed satisfactorily in cages, an additional nesting area, such as a nest box or boxes, is probably necessary.     

Vitamin E requirements of laying hens

In 5 experiments with 1,296 laying hybrids at the age of 22-73 weeks producing eggs for consumption a varied supplementation of between 0 and 20 mg vitamin E per kg of a semisynthetic ration was tested. The vitamin E content of the basal ration was less than 1 mg per kg feed. The quotas of selenium and unsaturated fatty acids in the feed were taken into consideration. Vitamin E and Se supplements did not influence, feed intake, laying, performance, feed efficiency/100 g egg development of body weight and mortality. The supplementation of 14% vitamin-E-free sunflower oil caused a significant decrease of the laying performance by 15%. There was no relation between the humoral immune reaction and vitamin E supply. The peroxide value of the abdominal fat and the activities of the creatine phosphokinase, the aspartate and alanine amino transferase in the blood serum were not directionally changed by the vitamin E, Se and oil supplements. There were no significant relations between the vitamin E content of the feed and that of the yolk and the yolk sac of the chicken. A vitamin E requirement of less than 1 mg and a requirement norm, including a safety margin, of 5 mg per kg feed was derived from the results for laying hens for egg production. A supplement of synthetic vitamin E to laying hen feed is thus not necessary.     

产蛋母鸡合理的营养方案

产蛋母鸡的合理营养对确保蛋鸡和鸡蛋生产企业获得最佳生产成绩非常重要。     

Optimum threonine requirement of laying hens

1. One experiment was conducted with medium weight laying hens to determine their threonine requirement between 28-38 weeks. 2. Two threonine-limiting diets of identical protein quality (summit-dilution) were used and, by dilution, ten protein contents were produced supplying 2.7 to 5.4 g total threonine/kg diet. The diet with the lowest protein was also supplemented with synthetic L-threonine. Each diet was fed to 5 groups of 24 laying hens. 3. The daily threonine requirement of the individual laying hens was estimated by direct methods to be 8.7 mg/g egg output plus 43.49 mg/kg body weight for this experiment. Calculated optimum intakes of threonine for various ratios of costs of input to value of output are tabulated. For example, for a flock of medium weight laying hens producing an average of 50 g daily egg mass, the optimum threonine intake (mg/hen d) varied between 700 and 710 for cost ratios (k-values) varying between 0.002 and 0.001.     

Effect of carbon dioxide stunning on somatosensory evoked potentials in hens

The spontaneous electroencephalogram (EEG) and somatosensory evoked potentials (SEPs) were examined in 17 hens before and during stunning in 45 per cent carbon dioxide. The results indicated that EEG suppression and loss of SEPs occurred in 21 +/- 4 s and 30 +/- 2 s, respectively, after exposure to carbon dioxide, eventually leading to EEG silence in 101 +/- 18 s. Convulsions occurred 15 seconds after the loss of SEPs, suggesting that the hens convulsed while they were unconscious. It is concluded that the induction of anaesthesia can be rapid in carbon dioxide stunning and in this respect carbon dioxide is potentially suitable for stunning poultry under commercial conditions.     

Effects of photoperiod on broodiness,egg-laying and endocrine responses in native laying hens

1. The effects of photoperiod on broodiness, egg-laying and endocrine responses in native laying hens were investigated. A total of 648, 18-week-old native laying hens (Beijing You Chicken, BYC) were randomly allocated to 6 groups with 3 replicates. The birds were exposed to 1 of 6 different photoperiods, including 16L:8D (06:00 to 22:00 h) for group 1; 12L:2D:4L:6D for group 2; 8L:4D:4L:8D for group 3; 16L:8D (03:00 to 19:00 h) for group 4; 14L:10D for group 5; and 18L:6D for group 6.

2. The broodiness rate and egg-laying rate for weeks 20–26, 27–33, 34–40, 41–47, 48–54 and 55–61 were calculated, and serum prolactin (PRL), luteinising hormone (LH), 17-beta-oestradiol (E2), melatonin (Mel) and progesterone (P4) concentrations were measured at the end of each stage.

3. Significant effects were observed on the rate of broodiness by the photoperiod and stage, but the interaction of photoperiod and stage was not significant. The rate of broodiness for group 3 (5.9%) was significantly higher than other groups, with group 2 being the lowest (2.8%). Broodiness rate was the highest for weeks 41–47 (9.9%). Significant effects were observed on average egg-laying rate by photoperiod and stage: the rate of egg-laying of groups 2 and 5 were significantly higher than groups 1, 4 and 6.

4. There were no significant effects of photoperiod on PRL, LH and Mel concentrations at 26, 33, 40 and 54 weeks of age (P > 0.05), but at 47 weeks of age, PRL and LH concentrations of group 1 were significantly lower than those in other groups.

5. The study suggests that the photoperiod of group 2 (12L:2D:4L:6D) is optimal for the birds’ performance to give the lowest broodiness rate and the highest egg-laying rate during the whole laying period, and 41–47 weeks may be a key stage for the photomodulation of broodiness.